Topalov won game eight to tie the match with four games to go. His win had more to do with Anand’s carelessness than it did with his own cleverness, but hey, a win is a win. The momentum has completely shifted to Topalov now. It will be interesting to see if Anand can get it together down the home stretch.

The game was another Slav. Once again Anand was the first to vary, but he got a bit careless in the queenless middlegame.

Position after 22. … f5-f4

Anand has just moved his f-pawn one square forward, attacking the white bishop on e3. Sadly, he seems to have missed a little trick.

Topalov played 23. Ne4! discovering an attack on the unprotected black rook on c8, and hitting the black bishop on g5. Anand went for his least bad option and play continued 23. … Rxc1 24. Nd6+ Kd7 25. Bxc1 and white has a real bind on the position. During the press conference after the game Topalov remarked that he though he was winning here, and Anand described his pawn move as a blunder. The computer is not quite so bullish on white’s position, though it does say white is considerably better.

Topalov did not play as incisively as he might have, and eventually traded down into one of those dreaded BOOC endings. That’s Bishop’s of Opposite Colors, mind you.

Position after 34. … Kc8-d7

These endings are notoriously drawn. The problem is that bishops can only move on squares of one color. In this position the white bishop plays exclusively on dark squares and the black bishop plays exclusively on white squares. That means they never come into contact with one another. Former World Champion Boris Spassky, when asked about his divorce, remarked sadly that he and his wife were like bishops of opposite colors. Never communicating. In this position black can set up a blockade on the light squares, and white lacks the firepower to break it down.

So let’s take stock of the position. White is up a pawn, but is it enough to win? Black has two pieces and three things to worry about. First, he must make sure the white d-pawn can not advance. Second, the black pawn on h7 is vulnerable. If it falls, the BOOC will not save him. Third, he must be ever vigilant about white’s attempts to invade with his king. With proper defense Black ought to be able to prevent all three.

Topalov probed and did his best, but Anand is an excellent endgame player. But even the best of us get tired, and he played a real howler in this position:

Position after 54. Kf4-g5

Twenty moves along and black’s defenses are holding. The black bishop keeps the white d-pawn at bay, and the black king is holding his own in the staring contest with his white counterpart. But now Anand played 54. … Bc6?? and after 55. Kh6 Kg8 56. g4 he resigned!

This is one of those positions you have to stare at for a while before you realize that black is toast. By playing his bishop to c6, Anand could no longer use the bishop to cover the h7 pawn. The correct move was 54. … Bd3! He would then march the king over to d7 to take over the babysitting duties on the white d-pawn. The black king is completely unbudgeable on d7, and black just shifts his bishop along the b1-h7 diagonal. What does white do? Dead draw.

This is zugzwang, which is fancy chess-speak for a position in which any move you make weakens your position. If black could just say “Pass” then all would be well. But the rules say that black must make every other move. He has no pawn moves, and his king is glued to the h-pawn. So that leaves 60. … Bc6 61. g6 hxg6 62. Kxg6 Be8+ 63. Kf6 Bc6 64. Bh6

Analysis Diagram

Game over. White’s king is in. Black is helpless.

What can you do? Blunders are part of the game. This has been a very exciting match so far. How will it end? Game Nine on Thursday!

“First, he must make sure the white d-pawn can not advance. Second, the black pawn on h7 is vulnerable. If it falls, the BOOC will not save him. Third, he must be ever vigilant about white’s attempts to invade with his king.”

and…

“54. … Bd3! He would then march the king over to d7 to take over the babysitting duties on the white d-pawn. The black king is completely unbudgeable on d7, and black just shifts his bishop along the b1-h7 diagonal. What does white do? Dead draw.”

Actually your analysis ignores White’s f and g pawns. I think after 54. … Bd3! White starts marching the f and g pawns up, creating a second passed pawn on the f file. That is what Anand was probably thinking about when he played his 54th move.

White can create a second passed pawn, but it looks like it should still be a draw. Imagine that white has pushed his f and g pawns, and that an exchange of pawns has occurred on f5. So black’s king is on d7, his bishop is on d3. White now has a pawn on f5 and his king is on g5. Black has the key move h6+. If white plays his king to f6, then he will never be able to advance his f-pawn since the king must always stay in contact with the pawn. If he moves his king to f4, then black transfers his bishops to the c4-g8 diagonal. Then the black bishop and h-pawn prevent the white king from supporting the advance of the pawn. So unless I have missed something it still should be an easy draw.

Okay, pawn at f5, Black plays h6+, White King to f4, Black Bishop to c4 (occupying c4-g8) diagonal, this is the position you presented.

Now White plays f6.

Now consider the position. Note that the d and f pawns and the White bishop form a structure that cannot be attacked by the White King, as if King takes bishop at least one of pawns queen. Basically Black King has to stay close to White’s d and f pawns to stop them from queening.

Now White King is free to roam. It attacks the Black h pawn. Once the h pawn is taken and it occupies the g7 square, at best Black will be able to give up Bishop for White’s d and f pawns. This still leads to a lost endgame for Black as with the aid of its Bishop, the White King
will eventually be able to kill the remaining Black pawns and queen the a or b pawns. It may also be possible that White can lose just the f pawn for Black’s bishop and queen the d pawn.